Melanoma is a malignancy of melanocytes located predominantly in the skin but also found in mucous membranes. The primary cause of malignant melanoma is ultraviolet light. Early signs of melanoma are the changes of size, colour and shape of the existing moles. Confirmation of the clinical diagnosis is done with a skin biopsy. Melanomas usually spread to the lymph nodes in the area of the tumour. Sentinel lymph node biopsy is generally indicated for pathologic staging of the regional lymph node. Traditional TNM (tumour – node - metastasis) classification system classifies melanomas on the basis of their characteristic. Stage I and II are localized primary melanoma. In stage III, there are metastases to single regional lymph node. Stage IV is the distant metastatic disease. Basic therapy of malignant melanoma is surgical excision with the adequate surgical margins. This is often done by a wide local excision with 1 to 2 cm margins. If a lymph node is positive, a radical lymph node dissection will often be performed.